1045 avenue de la Médecine
418.656.2131 extension 7597
The microbiome defines the collective genome or the microorganisms inhabiting a particular environment. We now realize that that the human microbiome plays a major role in human health. In a similar fashion, the planktonic microbiome, or the ensemble of microbes in natural waters and their function, play a predominant role in the health of aquatic ecosystems. It is at the base of the trophic chain and of biogeochemical cycles. It is generally considered that this microbiome is composed of bacteria, archaea, phytoplankton, protists and viruses. One of the most abundant groups in northern waters are picophytoplankton, more specifically picocyanobacteria or picoeukaryotes in marine ecosystems. For many years, populations of these autotrophic organisms have been analyzed by flow cytometry using the intrinsic fluorescence of their photosynthetic pigments. This type of instrument measures optical properties on a single cell basis allowing rapid sub-population identification in a sample. The obtained information can then be used to establish a limnological or oceanographic profile.
Albeit being used in field campaigns, these instruments are generally expensive and optimized for medical applications rather than environmental. Furthermore, they require very precise optical alignment and are poorly adapted for the harsh arctic conditions. To work around these issues, researchers are often required to preserve samples cryogenically until further analysis in laboratories several thousands of kilometers south of the sampling site. In addition, these manipulations do not allow to obtain a live overview of the microbiota while on the field, thus increasing risks associated with inadequate sampling.
Therefore, the goal of this project, as a part of Sentinel North 3.1 is to develop a portable flow cytometry platform for the analysis of picophytoplankton in northern environments. The technology used in this project, developed in Professor Denis Boudreau’s lab, aims at generating a virtual spatial encoding which allowing for a multiplexed, single detector measurement of the fluorescence signals from many photosynthetic pigments. This technique also allows increasing the signal-to-noise ratio compared to conventional flow cytometry. The use of a single detector ultimately simplifies the instrument thus reducing its energy consumption, weight and volume. With the objective of answering the needs of northern researchers, integrated photonic techniques and microfluidics are used in order to produce a simple, alignment free and compact flow cytometry system.